PRESTON: "Dr. Shepherd."DEREK: "Dr. Burke. Hey. Weâ€™ve known each other for a while."PRESTON: "Yes."DEREK: "Weâ€™ve done several successful surgeries together."PRESTON: "Yes."DEREK: "Your girlfriend is my ex-girlfriend's best friend."PRESTON: "Yes."DEREK: "So, why donâ€™t we call each other by our first names?"PRESTON: â€œI donâ€™t think so."[Later]ADDISON: "Hey, Preston."PRESTON: "Good to see you, Addison!"DEREK: "She gets to call you by your first name and I don't?"PRESTON: "I like her."DEREK: "You don't like me?"PRESTON: "No."